TY - JOUR

T1 - Thermotolerant cyclamen with reduced acrolein and methyl vinyl ketone

AU - Kai, Hiroomi

AU - Hirashima, Keita

AU - Matsuda, Osamu

AU - Ikegami, Hidetoshi

AU - Winkelmann, Traud

AU - Nakahara, Takao

AU - Iba, Koh

N1 - Funding Information: We thank Dr Thomas D. Sharkey for his critical review of the manuscript, and Dr Akihiko Ito, Mrs Yu Shimizu, and Michio Tajima for helpful discussions. We also thank Mr Tetsuro Kage and the companies Morel Diffusion S.A.S., Goldsmith, Varinova, Schoneveld Twello B.V., and Syngenta Seeds for supplying cyclamen seeds. This work was supported by a Grant-in-Aid for Scientific Research on Innovative Areas (no. 21114002) from the Ministry of Education, Science and Culture of Japan, and by the Program for Promotion of Basic and Applied Researches for Innovations in Bio-oriented Industry (BRAIN).

PY - 2012/6

Y1 - 2012/6

N2 - Reduced levels of trienoic fatty acids (TAs) in chloroplast membranes induce thermotolerance in several plant species, but the underlying mechanisms remain unclear. TA peroxidation in plant cell membranes generates cytotoxic, TA-derived compounds containing α,β-unsaturated carbonyl groups. The relationship between low TA levels and the amounts of cytotoxic TA-derived compounds was examined using thermotolerant transgenic cyclamen (Cyclamen persicum Mill.) with low TA contents. Changes in the levels of the cytotoxic TA-derived acrolein (ACR), methyl vinyl ketone (MVK), (E)-2-hexenal, 4-hydroxy-2-nonenal, and malondialdehyde were analysed in the leaf tissues of wild-type (WT) and thermotolerant transgenic cyclamen under heat stress. Levels of ACR and MVK in the WT increased in parallel with the occurrence of heat-induced tissue damage, whereas no such changes were observed in the thermotolerant transgenic lines. Furthermore, exogenous ACR and MVK infiltrated into leaves to concentrations similar to those observed in heat-stressed WT leaves caused similar disease symptoms. These results suggest that thermotolerance in transgenic cyclamen depends on reduced production rates of ACR and MVK under heat stress, due to the low level of TAs in these plants.

AB - Reduced levels of trienoic fatty acids (TAs) in chloroplast membranes induce thermotolerance in several plant species, but the underlying mechanisms remain unclear. TA peroxidation in plant cell membranes generates cytotoxic, TA-derived compounds containing α,β-unsaturated carbonyl groups. The relationship between low TA levels and the amounts of cytotoxic TA-derived compounds was examined using thermotolerant transgenic cyclamen (Cyclamen persicum Mill.) with low TA contents. Changes in the levels of the cytotoxic TA-derived acrolein (ACR), methyl vinyl ketone (MVK), (E)-2-hexenal, 4-hydroxy-2-nonenal, and malondialdehyde were analysed in the leaf tissues of wild-type (WT) and thermotolerant transgenic cyclamen under heat stress. Levels of ACR and MVK in the WT increased in parallel with the occurrence of heat-induced tissue damage, whereas no such changes were observed in the thermotolerant transgenic lines. Furthermore, exogenous ACR and MVK infiltrated into leaves to concentrations similar to those observed in heat-stressed WT leaves caused similar disease symptoms. These results suggest that thermotolerance in transgenic cyclamen depends on reduced production rates of ACR and MVK under heat stress, due to the low level of TAs in these plants.

KW - Acrolein

KW - Cyclamen persicum Mill.

KW - Methyl vinyl ketone

KW - Thermotolerance

KW - Trienoic fatty acids

UR - http://www.scopus.com/inward/record.url?scp=84866706123&partnerID=8YFLogxK

U2 - 10.1093/jxb/ers110

DO - 10.1093/jxb/ers110

M3 - Article

C2 - 22511805

AN - SCOPUS:84866706123

VL - 63

SP - 4143

EP - 4150

JO - Journal of experimental botany

JF - Journal of experimental botany

SN - 0022-0957

IS - 11

ER -